Question: What is the official language of the First Bulgarian Empire where the alphabet is the Early Cyrillic alphabet?
Paraphrase: What is the professional language of the First Bulgarian Empire the place the alphabet is the Early Cyrillic alphabet?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q203817 wdt:P37 ?answer . ?answer wdt:P282 wd:Q442244}
Answer: Old Church Slavonic